FIELD OF INVENTION
[0001] The invention relates to piston-type machines, and particularly to machines provided
with a conrod-free mechanism intended for transforming the translational motion of
pistons to the rotary motion of an output shaft.
[0002] Hereinafter the term "machine" means a device that is capable of performing functions
of both an engine and a pump. The term "engine" means a device intended for transforming
the energy of a working fluid to the mechanical energy, and particularly internal
combustion engines, steam engines, hydraulic engines etc. The term "pump" means a
device intended for forcing or compressing fluids by mechanical means, and particularly
both pumps for fluids and compressors for forcing compressible media, i.e. gases or
vapors.
[0003] The inventive solution relates to a piston-type machine in the general meaning thereof,
and may be used both in engines and in pumps.
BACKGROUND OF THE INVENTION
[0004] Well-known in the art is the kinematic layout of the slider-crank mechanism, implementing
a conrod-free mechanism intended for transforming the translational motion of pistons
to the rotary motion of an output shaft. The layout comprises a housing member provided
with two cylinders with mutually perpendicular axes; pistons with piston rods; sliders
provided on piston rods; slider guide members; a carrier member, and an intermediate
member engaged in rotary pairs with rods and with the carrier member.
[0005] In the course of reciprocal motion of pistons, the intermediate member pivotally
connected to cylinder rods and the carrier member, carries out a complicated plane-parallel
motion, thereby providing relationship between the motion of pistons and the rotation
of the carrier member, with transformation of the reciprocal motion of pistons to
the rotary motion of the carrier member without the use of connecting rods.
[0006] The above kinematic layout serves as a base for development of a conrod-free internal
combustion engine known as "Balandin engine" (S.S. Balandin, Conrod-free Internal
Combustion Engines, Moscow, Mashinostroyenie, 1968, pp.1∼15). This engine comprises
a housing member provided with cylinders; pistons with piston rods; sliders provided
on piston rods; slider guide members each being connected to the housing member and
made for displacing a corresponding slider along the axis of a corresponding cylinder;
two coaxial carrier members mounted inside the housing member, and a crankshaft disposed
between the carrier members, main journals of the above crankshaft being pivotally
connected to carrier members, and rod pins, to relevant piston rods.
[0007] In the course of reciprocal motion of pistons, the crankshaft that is pivotally connected
to cylinder rods and carrier members, carries out a complicated planetary motion by
rotating around its own axis and the axis of carrier members, and provides the relationship
between the reciprocal motion of the pistons and the rotation of the carrier members,
with transformation of the reciprocal motion of pistons to the synchronous rotary
motion of the carrier members without the use of connecting rods. Here, the main journals
of the crankshaft are moving along a circle with a radius equal to 1/4 stroke of the
pistons, while pistons and rods connected to the rod pins of the crankshaft are carrying
out only the rectilinear reciprocal motion along the stroke of pistons, without exerting
any lateral thrust against cylinder walls. This mechanism may be used not only for
internal combustion engines but also for driven compressors, pumps, piston gas generators,
and other piston-type machines. The engine with a similar kinematic layout is also
described in SU, A1, 118471.
[0008] In the course of practical implementation of the above devices, there occurs the
problem of design of guide members that would permit, when assembling the engine,
to adjust these guide members to a position ensuring a coordinated motion of pistons
inside cylinders and sliders/rods in the guide members without any distortions and
jamming of the mechanism. This problem acquires a critical importance from the standpoint
of the technological effectiveness of assembling of a piston machine, particularly
a multicylinder piston machine.
[0009] Also known in the art is a piston-type machine disclosed in the specification to
SU, A1, 1216271. This machine comprises a housing member provided with cylinders and
having an axial hole; liners mounted inside the cylinders; pistons with piston rods,
disposed inside the liners; sliders provided on piston rods; slider guide members
each provided for displacement of a corresponding slider along the axis of a corresponding
cylinder; two coaxial carrier members mounted inside the housing member, and a crankshaft
disposed inside the axial hole of the housing member between the carrier members,
main journals of the above crankshaft being connected to carrier members, and rod
pins, with relevant piston rods. Slider guide members are made integrally with the
liners and constitute an extension of the internal surface of the liner. That is,
each of the guiding surfaces for a corresponding slide comprises a structural member
of a corresponding liner, in which the guiding surface for the slider constitutes
an extension of the internal surface of the liner.
[0010] The reciprocal motion of pistons in this known piston-type machine is transformed,
through the rods with sliders moving within guide members, to the planetary rotary
motion of the crankshaft that is pivotally connected to the rods and carrier members.
The planetary motion of the crankshaft causes synchronous rotary motion of the carrier
members. During machine operation in the engine mode, the power may be picked up from
any carrier member or from an additional shaft being in kinematic relationship with
the carrier members and providing synchronization of the rotary motion of the carrier
members.
[0011] In this case, guide members for sliders are made non-adjustable. The accuracy of
location of the guiding surfaces is ensured in the process of liner manufacture, since
the slider guide members are made integral with the liners, constitute the extension
of the liner internal surface, and are made in a single run.
[0012] However, in this embodiment of the piston-type machine the distance between the guiding
surfaces restricting the displacement of each slider should not exceed the diameter
of liners since the guiding surfaces of sliders constitute the extension of the liners
internal surfaces comprising guiding surfaces for the pistons. From this, it follows
that in the above design which inevitably provides the planetary motion of the crankshaft
within the limits of the distance between the guiding surfaces of sliders, there exist
restrictions for the eccentricity of a crankshaft, and hence for the stroke length
of each piston. This circumstance substantially restricts the possibilities of Using
the above design in piston-type machines since it does not permit to provide a required
ratio between the cylinder diameter and the value of piston stroke length. It is of
special importance in the designs of internal combustion engines, and particularly
in diesel engines.
[0013] Known in the prior art are designs of piston-type machines provided with adjustable
guide members of piston rods. Thus, known in the art is a crank mechanism of a piston
type machine, disclosed in SU, A1, 1513259. This mechanism comprises a housing member
with a cylinder; a piston with a piston rod; a slider provided on the piston rod;
a slider guide member connected to the housing member and provided for slider displacement
along the cylinder axis; a carrier member; and a con-rod pivotally connected to the
slider and to the journal of the carrier member. Naturally, in a multipiston machine
the above crank mechanism is repeated for each piston group. The slider guide member
is shaped as a platelet mounted on the housing member for displacement and fixation
in a selected position by means of screws and nuts. Suspended from this platelet by
means of bolts and disk springs is a clamp member provided with solids of revolution.
The solids of revolution are mounted on the clamp member for interaction with flat
contact surfaces provided on the slider.
[0014] In this mechanism, the reciprocal motion of the piston is transformed to the rotary
motion of the crankshaft via the rod provided with a slider that is moving in the
guide member, and then via the con-rod. Here, flat contact surfaces of the slider
interact with the solids of revolution that are fastened to the clamp member, transmitting
the forces created thereby via disk springs and platelet to the housing member. In
case of a need to adjust the position of a guide member, the platelet is moved by
means of screws to a required position with respect to the housing member, following
which the platelet is fixed in the selected position by means of nuts.
[0015] In the above design, the procedure of setting the guide members supposes manual adjustment
of each guide member to the required position with respect to the axes of relevant
cylinders and contact surfaces of sliders; therefore, under real conditions of assembling
a piston-type machine it is practically impossible to attain a required accuracy of
setting all the guide members to prevent jamming of the mechanism. In addition, the
presence of console components and threaded joints in the power chain of the guide
member restricts the use of the guide member under consideration under conditions
of high dynamic loads, particularly in internal combustion engines, and especially
in diesel engines.
[0016] Known in the art are practical designs of conrod-free internal combustion engines
constructed in accordance with the "Balandin design". (S.S. Balandin, Conrod-free
Internal Combustion Engines, Moscow, Mashinostroyenie, 1968, pp.2875). These include
a four-cylinder engine developed for the purpose of testing major kinematic and design
properties of the conrod-free layout and performance of the conrod-free power mechanism
in the engine system under actual loads, as well as standardized conrod-free engines
having 140 to 400 hp power rating. Page 39 of this book contains the description of
a four-cylinder, four-stroke gasoline engine of the aircraft type. This known engine
comprises a housing member provided with cylinders, a front portion, a medium portion,
and a back lid. The front portion accommodates the carrier member of a conrod-free
mechanism, transmitting the engine power to a consumer, and a gas distribution mechanism.
Mounted in the back lid is another carrier member of the conrod-free mechanism. The
medium portion accommodates, between carrier members, a crankshaft with rods of the
conrod-free mechanism. Main (extreme) journals of the crankshaft are connected to
carrier members, and rod pins, to relevant piston rods. Each rod is provided with
a slider that is mounted in guide members. Each guide member is connected to the housing
member and is made for displacing a relevant slider along the axis of a corresponding
cylinder. All the parts of the engine are connected therebetween by studs. Guide members
for each slider are made as two separate segments, each segment being provided with
a guiding surface and fastened to the housing member by means of bolted joints so
that the guiding surfaces of the above segments, when being situated in parallel,
form a guiding structure that ensures the motion of a corresponding slider along the
axis of a relevant cylinder. Adjustment of guide members and provision of accuracy
of such adjustment are carried out by hand, in the process of assembling, by fitting
each segment to corresponding contact surfaces of sliders in a certain position, followed
by fastening of segments to the housing member by means of bolted joints.
[0017] During the working cycle, each piston carries out reciprocating motion within a corresponding
cylinder. Piston rods are moving together with pistons; in so doing, rod sliders are
moving in the guide members through which they transfer resulting lateral loads to
the housing member. Piston rods, being in the pivoted joint with the crankshaft, put
it in the planetary motion during which the crankshaft rotates around its axis and
around the axis of carrier members, thereby putting in the rotary motion the carrier
members; each of these carrier members can be the output shaft of the engine.
[0018] The above design is complicated to assemble since it is required to fit each guiding
segment, thereby ensuring the parallel arrangement of the guiding surfaces of segments
and their orientation relative to the axes of corresponding cylinders. Precise adjustment
of all the guiding segments, minimizing the probability of mechanism jamming, in this
embodiment is extremely difficult and under real conditions of assembling a piston-type
machine with conrod-free mechanism is practically unattainable.
BRIEF DESCRIPTION OF THE INVENTION
[0019] The invention is based upon the object to develop an improved piston-type machine
with conrod-free mechanism, in which design features would provide the possibility
of self-adjustment of slider guide members to an optimal position relative to axes
of corresponding cylinders in the course of assembling, thereby reducing the probability
of jamming of the mechanism, improving the technological effectiveness of the resulting
device, and substantially simplifying the assembling process.
[0020] The object set forth is attained in that in a piston-type machine with conrod-free
mechanism, comprising a housing member provided with cylinders; pistons with piston
rods; sliders provided on piston rods; slider guide members each being connected to
the housing member and made for displacing a corresponding slider along the axis of
a corresponding cylinder; two coaxial carrier members mounted inside the housing member,
and a crankshaft disposed between the carrier members, main journals of the above
crankshaft being pivotally connected to carrier members, and rod pins, to relevant
piston rods, according to the invention, each guide member is made as a ring-shaped
member with guiding surfaces, each ring-shaped member being mounted within the housing
member in coaxial relationship with carrier members for rotating around the axis of
said carrier members, and provided with means for fixing position thereof relative
to the housing member.
[0021] In the preferred embodiment of the invention, the guiding surfaces on each ring-shaped
member may be formed by parallel surfaces of a groove provided in the diametral direction
on one of the side surfaces of the ring-shaped member for displacement of the slider
along said groove.
[0022] The means for fixing each ring-shaped member relative to the housing member are expedient
to be provided as a screw joint wherein a threaded hole is disposed in the ring-shaped
member and the screw is mounted in a corresponding hole provided in the housing member,
diameter of said hole exceeding the diameter of said screw by 1.02 to 1.2 times.
[0023] In addition, it is also expedient to provide the means for fixing each ring-shaped
member as a screw joint wherein said threaded hole is disposed in the housing member
and the screw is mounted in a hole provided in the ring-shaped member, diameter of
said hole exceeding the diameter of said screw by 1.02 to 1.2 times.
[0024] Providing slider guide members as ring-shaped elements, mounting the ring-shaped
members within the housing member in coaxial relationship with carrier members for
rotation around the axis of carrier members, and fixing position thereof relative
to the housing member ensures the possibility of self-adjustment of the slider guide
members relative to the axes of corresponding cylinders. In the process of assembling
the inventive machine, the mounting of carrier members, crankshaft, pistons with piston
rods, and slider guide members is followed by the motoring of the mechanism, during
which the ring-shaped guide members, while rotating in mounting seats thereof around
the axis of carrier members, independently occupy the most optimal position to prevent
the jamming of the mechanism, following which they are fastened inside the housing
member with the use of available means for fixing.
BRIEF DESCRIPTION OF DRAWINGS
[0025] The inventive piston-type machine with conrod-free mechanism is further described
in more detail and with reference to the accompanying drawings, in which:
- Fig. 1
- is a general view of the inventive piston-type machine with conrod-free mechanism,
cross-section.
- Fig. 2
- is section II-II of the piston-type machine with conrod-free mechanism, shown in Fig.1.
- Fig. 3
- is section III-III of the piston-type machine with conrod-free mechanism, shown in
Fig.1.
- Fig. 4
- is axonometric view of the piston group.
- Fig. 5
- is an embodiment of the means for fixing guide members.
- Fig. 6
- is section VI-VI of the piston-type machine with conrod-free mechanism, shown in Fig.1.
BEST EMBODIMENT OF THE INVENTION
[0026] As it is shown in Figs 1 through 4, the inventive piston-type machine with conrod-free
mechanism comprises housing member 1 provided with cylinders 2, tunnel hole 3 and
flange cover 4, and pistons 5 provided with piston rods 6. Carrier members 7 are coaxially
mounted inside housing member 1. Carrier members 7 have main journals 8 and eccentric
holes 9. Disposed between carrier members 7 is crankshaft 10 whose main journals 11
are pivotally connected to carrier members 7, while rod pins 12 are pivotally connected
to corresponding piston robs 6 via sliders 13 provided on piston rods 6. Each of sliders
13 is mounted in a guide member made in the form of ring-shaped member 14 provided
with guiding surfaces 15 made for displacing a corresponding slider 13 along the axis
of a corresponding cylinder 2.
[0027] Each ring-shaped member 14 is connected to housing member 1 for rotation thereof
around axis 16 of carrier members 7 and is provided with means for fixing position
thereof relative to housing member 1. Guiding surfaces 15 on ring-shaped member 14
are made in the form of a groove disposed diametrically on one of the sides of ring-shaped
member 14 for displacement of slider 13 along said groove. Means for fixing each ring-shaped
member 14 relative to housing member 1 are made in the form of a screw joint wherein
threaded hole is made in ring-shaped member 14, and screw 18 is mounted in hole 19
provided in housing member 1 whose diameter exceeds the diameter of screw 18 by 1.02
to 1.2 times. Also possible is the embodiment of the screw joint wherein ring-shaped
members 14 are provided with flanges 20 (Fig.5) having holes 21 for mounting screws
18, and threaded holes 22 are made in housing member 1. Carrier members 7 are provided
with gear rings 23, 24 that are in engagement with pinions 25, 26. Pinions 25, 26
are connected to synchronizing shaft 27 (Fig.6). The presence of synchronizing shaft
27 in the machine design ensures synchronous rotation of carrier members 7 and prevents
jamming of crankshaft 10 in its pivoted joints with carrier members 7. Piston rods
6 are connected to sliders 13 by means of threaded joint 28.
[0028] The procedure used for assembling the piston-type machine is as follows. Each of
sliders 13 is mounted between guiding surfaces 15 of ring-shaped members 14. Crankshaft
10 is placed in the hole of one slider, and the first of carrier members 7 is mounted
so as to ensure location of main journal 8 of carrier member 7 within the mounting
seat of ring-shaped member 4, and main journal 11 of crankshaft 10, inside eccentric
hole 9 of carrier member 7. Following this, successively disposed on crankshaft 10
are other sliders 13 in assembly with ring-shaped members 14 serving as guides. Then
the second carrier member 7 is mounted with the use of the same rules of assembling
as those used for mounting the first carrier member 7. Sliders 13 are disposed within
guiding surfaces 15 so that they do not protrude beyond the limits of the maximum
diameter of ring-shaped members 14. The thus assembled parts are mounted into tunnel
hole 3 in housing member 1. In so doing, ring-shaped members 14 are disposed in corresponding
mounting seats provided in housing member 1, for rotation around axis 16 of carrier
members 7. After this, flange cover 4 is mounted. Screws 18 are mounted into threaded
holes 19 or 22 (second option) without tightening. Sliders 13 are connected to piston
rods 6 by means of threaded joint 28. Then synchronizing shaft 27 is mounted so that
pinions 25, 26 come into engagement with gear rings 23, 24 of carrier members 7. Following
this, the motoring of the mechanism is carried out, during which ring-shaped guide
members 14, being the guide of sliders 13, are self-adjusted and occupy the optimal
position relative to the axes of cylinders 2, wherein the probability of jamming of
the mechanism is minimal. Position of ring-shaped members 13 is fixed by tightening
screws 18. The mechanism is ready for operation.
[0029] The piston-type machine a conrod-free mechanism operates as follows.
[0030] During the working cycle, each piston 5 carries out reciprocating motion within a
corresponding cylinder 2. Piston rods 6 provided with sliders 13 are: moving together
with pistons 5; in so doing, sliders 13 of piston rods 6 are moving between guiding
surfaces 15 of ring-shaped members 14 through which they transfer resulting lateral
loads to housing member 1. Piston rods 6, being in the pivoted joint with crankshaft
10, put it in the planetary motion during which crankshaft 10 rotates around its axis
and around axis 16 of carrier members 7, thereby putting in the rotary motion carrier
members 7. Synchronization of the rotation of carrier members 7 is carried out by
means of synchronizing shaft 27 connected to pinions 25, 26 that are in engagement
with gear rings 23, 24 of carrier members 7. Engine power may be picked up from any
carrier member 7 or from synchronizing shaft 27. During operation of the piston-type
machine in the engine mode, the energy of working fluid supplied to cylinders 2 is
transformed to mechanical energy. During operation of the piston-type machine in the
pump or compressor mode, forced rotation of carrier members 7 results in injection
or compression of fluids by piston groups.
[0031] The inventive piston type machine with conrod-free mechanism is characterized by
a high technological effectiveness of design and simple procedure of assembling during
which slider guide members occupy an optimal position due to their self-adjustment
relative to the axes of corresponding cylinders, which fact permits to minimize the
probability of mechanism jamming in the operating mode.
INDUSTRIAL APPLICABILITY
[0032] The proposed mechanism may be used in a variety of piston-type machines that require
high load capacity, high mechanical efficiency, good balance (minimum vibrations),
and compactness. First of all, such machines include automotive and aircraft piston-type
engines, and particularly diesel engines, marine and locomotive diesels. engines of
farming, construction, and other kinds of machinery.
1. A piston-type machine with conrod-free mechanism, comprising a housing member provided
with cylinders; pistons with piston rods; sliders provided on said piston rods; slider
guide members each being connected to said housing member and made for displacing
a corresponding slider along the axis of a corresponding cylinder; two coaxial carrier
members mounted inside said housing member, and a crankshaft disposed between said
carrier members, extreme journals of said above crankshaft being connected to said
carrier members, and medium journals, to corresponding piston rods pins, wherein,
each guide member is made as a ring-shaped member with guiding surfaces, each ring-shaped
member being mounted within said housing member in coaxial relationship with said
carrier members for rotating around the axis of said carrier members, and provided
with means for fixing position thereof relative to said housing member.
2. A piston-type machine as set forth in claim 1, wherein said guiding surfaces on each
ring-shaped member are formed by parallel surfaces of a groove provided in the diametral
direction on one of side surfaces of said ring-shaped member for displacement of said
slider along said groove.
3. A piston-type machine as set forth in claim 1, wherein means for fixing each ring-shaped
member relative to said housing member comprise a screw joint wherein a threaded hole
is disposed in said ring-shaped member and the screw is mounted in a hole provided
in said housing member, diameter of said hole exceeding the diameter of said screw
by 1.02 to 1.2 times.
4. A piston-type machine as set forth in claim 1, wherein said means for fixing each
ring-shaped member relative to said housing member comprise a screw joint wherein
said threaded hole is provided in said housing member and said screw is mounted in
a hole provided in said ring-shaped member, diameter of said hole exceeding diameter
of said screw by 1.02 to 1.2 times.